Atom-thick 'nanosheets' could lead to future tech

An international team of physicists, led by researchers at
Oxford University and Trinity College Dublin, have invented a fast,
simple and inexpensive way of splitting layered materials to create
one-atom thick "nanosheets".

The idea is to explore materials which have unique chemical and electronic properties, and would be perfect for
electronic devices and super-strong composite materials. Other than
current-favourite graphene -- an atom-thick sheet of carbon -- that
is.

Graphene is an atom-thick material which has extraordinary
electrical properties. It's something of a scientific celebrity of
late, getting heaps of attention since Manchester physicists Andre
Geim and Konstantin Novoselov won last year's Nobel Prize for
Physics for their work on the material.

"Graphene has been getting all the attention," says Dr
Valeria Nicolosi of Oxford University's Department of Materials.
"But in fact there are hundreds of other layered materials that
could enable us to create powerful new technologies."

There are over 150 of these materials, such as boron
nitride, molybdenum disulfide, and tungsten disulfide, which could
be metallic, semi-metallic or semiconducting depending on the
arrangement of their atoms or chemical composition. Harnessing
those unique properties would give physicists incredible new
materials for future technologies.

For decades, however, any attempt to arrange them in
atom-thick layers has been laborious and time consuming, and the
resulting materials were fragile and useless in most applications.
The team's new method is cheap, fast and spits out a lot of very
tough materials.

"Within a couple of hours, and with just 1 mg of material,
billions and billions of one-atom-thick graphene-like nanosheets
can be made at the same time from a wide variety of layered
materials," said Dr Nicolosi.

These nanosheets, with their exotic and unique abilities,
can be integrated with conventional technologies just by spraying
them onto other materials, like silicon. They then have the potential to lead to new designs of
computing devices, sensors or batteries.

A full report of the research, "'Two-dimensional nanosheets
produced by liquid exfoliation of layered materials," will appear
in the 4 February edition of the journal
Science.